1. Field of the Invention
The invention relates to a pressure-balanced mechanism for a print head, and more particularly to the pressure-balanced mechanism that can provide a three-point equilibrium forcing pattern having a pivot point and two depression points to improve the printing quality.
2. Description of the Prior Art
In daily life, in order to rapidly and concisely communicate merchandise information, a printing apparatus is usually applied to mass print out the information in a paper form, either to be posted on the merchandises or to be flowed in some other necessary places. For example, the paper-form information can include merchandise tags, bar codes, receipts and any paper the like to record the merchandise information.
In practical application, various retailers and/or various merchandises always have their own tags, bar codes or receipts printed on specific papers. Namely, the sticker papers or the thermal papers as the carrier bodies fed to the printing apparatuses would vary in widths and sizes. Thus, to meet this situation, current printing apparatuses are generally manufactured to fixed specs for matching various-spec carrier bodies.
Nevertheless, though current printing apparatuses may be suitable to carrier bodies with varying widths and sizes, yet it does not mean that the printing apparatuses make changes or adjustments to meet different carrier bodies. Consequently, an obvious and inevitable shortcoming of the current printing apparatuses is that, while in meeting some carrier bodies or after a specific service time, the print head of the printing apparatus would generate non-uniform printing, both in coloring and in lining, due to the unbalanced forcing at the print head. Definitely, any improvement upon this shortcoming for either the current printing apparatus or the print head would be welcome to the art.